Last week, at a Senate hearing concerning the Toyota recalls, transportation secretary Ray LaHood said the government may recommend that all cars have smart pedals in the future.
“The smart brake pedal removes the power from the engine so you can slow the car down more quickly,” says Thomas Plucinsky, a product manager at BMW of North America. BMW’s cars have included a brake-override system since 1988. The system uses two solid-state position sensors in the brake pedal and one in the accelerator. Chrysler also has smart pedals in about 97 percent of its cars. Its system causes a car to go into a reduced-power mode after about two to four seconds when both pedals are pressed. Other car companies, including Mercedes-Benz, Volkswagen, and Nissan, have had brake overrides in their cars for years.
Toyota’s brake-override system uses the accelerator pedal position sensor, the vehicle speed sensor, and the brake light circuitry. When the system senses that both the brake and gas pedal are activated–as might happen when a floor mat edge holds the accelerator in place and the driver is trying to brake–it reduces the engine to idle speed. The smart pedal activates when the accelerator pedal is depressed at least 25 percent and the car is moving more than five miles an hour, says Lyons. This way it knows not to activate when a driver is doing a hill start (easing off the brake as the accelerator is slowly pressed) or if a driver momentarily taps the brake pedal while accelerating. “It’s a very smart system and completely unobtrusive,” says Lyons.
Not everybody’s convinced. Sean Kane, founder of Safety Research & Strategies, is skeptical that Toyota’s smart pedal solution really addresses the problem. “It doesn’t seem to me that this application will accomplish what it needs to,” he says.
If a driver whose car has a smart pedal is in a situation when the system need to be activated, Plucinsky’s advice is: “Apply the brake quickly. Press as hard as you can to stop quickly and switch into neutral.”
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